Priority: P1: Critical
Resolution: Out of scope
Affects Version/s: 5.12.0 Beta 1, 5.12.0
Fix Version/s: None
Environment:openSUSE Tumbleweed x86-64: 20190115 (can repro from 20181214+)
Linux 4.19.12 (openSUSE kernel-default)
xf86-video-intel: git 25c9a2fcc
Intel HD Graphics 4000 (i5-3317U)
After updating Qt to 5.12.0, if compositing is enabled and set to OpenGL 2.0/3.1, significant flickering will show across the whole desktop.
Users have reported this issue does not occur in the following cases:
- Rendering backend is set to XRender
- Vsync is fully disabled (None)
- xf86-video-modesetting driver is used
- Plasma Wayland is used
Most reports have been with Intel graphics, but there are a couple of reports with Nouveau as well.
Bisecting the issue points to commit 60cecc86f8 (xcb: Initialize OpenGL integration only when required). Recompiling 5.12.0 with the commit reverted stops the issue from occurring.
Downstream bug report: https://bugzilla.opensuse.org/show_bug.cgi?id=1120090